A measurement is often carried out for obtaining the communication performance, such as receiving sensitivity or radiation power, including the antenna characteristics of mobile communication equipment such as a cell phone, a communication equipment built-in notebook personal computer and the like. At the measurement, it may be important to clarify the influence on an antenna from the circuit and the structure of the mobile communication equipment as an object to be measured in an anechoic chamber.
In measuring communication performance of mobile communication equipment as mentioned above, spherical measurement is adopted to measure the electromagnetic field emitted from the communication equipment over a spherical surface around measured equipment (equipment to be measured), thereby the measurement at all solid angles around the communication equipment may be permitted.
Japanese Laid-open Patent Publication No. 2008-89567 has proposed a technique of measuring antenna radiation characteristics by concentrating the radiation power from a measured antenna (an antenna to be measured) on an upper semispherical surface using a reflector. Japanese Laid-open Patent Publication No. 2005-61949 has proposed an electromagnetic wave measuring box that the inside of a shield chamber is shaped into a spherical form using a reflector.